Trawling the sea bed

摘要

The issue of dredging for harvesting of demersal and benthic species has been raised with increasing frequency and urgency by several groups of scientists in the past few years. Despite this, the effects of sea bed dredging and trawling on habitats and species are still insufficiently understood and, probably, the matter still does not have a sufficiently high profile. As so often is the case with extractive industries, differences of views are stark. One potentially important view has recently been stated in an FAO document (Lokkeberg, 2005) which, heavily paraphrased, suggests that the biological effects of dredging are not statistically examined sufficiently to justify claims that effects are great. It also suggests that much of the available data do not show damage or significant changes to benthic species, to their composition or to their habitats, and the document suggests that sampling methods used in the past are often inappropriate. In this issue of Marine Pollution Bulletin, a Viewpoint by Gray et al. (2006) examines that particular FAO document in detail. The latter authors clearly show that much of the FAO's central theme (assuming that FAO endorses its own document) is arguable.